Under pressure: how specialist eye care changed outcomes for glaucoma patients
Gary Finnegan asks consultant ophthalmologist Keith Barton how glaucoma care has changed over the past 20 years and what the future holds
Outcomes for glaucoma patients are better than ever thanks to specialisation in ophthalmology and advances in diagnostics, medication and surgery. ‘Since the 1990s we have seen increasing sub-specialisation in ophthalmology,’ says Dr Keith Barton. ‘The change has been particularly dramatic for glaucoma where general ophthalmologists had provided care for most patients, while specialists only saw complex cases.’
This progress coincided with a steady growth in the number of patients with suspected glaucoma, which causes damage to the eye’s optic nerve and gets worse over time. The condition is caused by a build-up of pressure inside the eye and the risk of developing glaucoma is higher in people aged over 40 or who have diabetes. Timely diagnosis and treatment can reduce the pressure before serious damage is done to the patient’s vision.
‘There was great innovation in medical therapy in the late 1990s, leading to a sea change in how we treat glaucoma,’ recalls Dr Barton. ‘That has since slowed down, shifting the focus onto new ways to deliver drugs.’
Diagnosis, medication, surgery
Diagnostic and imaging technologies play an important role in detecting glaucoma and helping experts decide how it should be managed. Most decisions are made on the basis of the patient’s visual field and measurements of the pressure in their eye, but the development of higher resolution optical coherence tomography (OCT) could help too.
There is also considerable progress under way in glaucoma surgery, a field which previously received much less attention from researchers and industry. ‘Glaucoma surgery was a graveyard of innovation for years – with some notable exceptions – but there has been a deluge of new devices recently, mainly for addressing earlier stages of glaucoma.’
These include tiny stents that can alleviate pressure in the eye, canaloplasty which helps drain fluid, and micropulse laser surgery, amongst others.
‘There was an unmet need but, in the past, there may not have been sufficient patient numbers to attract innovation in surgery because most patients were treated with eyedrops,’ says Dr Barton. ‘What has changed is that there has been a sudden realisation that a significant percentage of cataract patients have glaucoma.’
Tackling cataracts and glaucoma
Now, some cataract patients can have a pressure-lowering device, such as a tiny titanium stent, inserted during their cataract surgery. The attraction of this approach is that surgeons can kill two birds with one stone – removing a cataract and addressing glaucoma in a single operation.
The result for suitable patients can be a reduced reliance on medication, including daily eyedrops. The impact varies from patient to patient: instead of taking three glaucoma medications for the rest of their life some patients may need two; or if there on two drugs, they not need none after the operation.
‘It can reduce dependence on eyedrops, which is important given the compliance issues we face with any lifelong medication,’ Dr Barton says. Patients sometimes forget to take their daily drops; they become complacent about the risk to their sight; or they dislike the odour of some eyedrops.
Adding a tiny pressure-reducing implant during cataract surgery brings some additional cost but takes just five minutes longer. Depending on the age of the patient and the success of the treatment, there may be real benefits in reducing the use of daily medication, which in itself represents a quality-of-life boost for the patient.
An eye on the future
Looking ahead, researchers are exploring a range of areas including slow-release medication systems, sensors that continuously measure eye pressure, approaches to reducing cell death in the eye, and stem cell implants.
‘20 years ago, stem cell implants for glaucoma were seen as science fiction,’ says Dr Barton. ‘Now it is still some way off but we can see that it is on the horizon. It’s a matter of time.’